Overdriving the output of a Hydro? Has anyone did it and how long did it last?

I searched the forum and found this same question, but not an answer. I've got a 26HP VT BS in a 54 inch Husqvarna with a hydro. I'd like to build an ATU for the G/F to use around the farm but faster than a normal mower speed. I was thinking about building a frame with the hydro driving another axle behind the hydro with the second axle "split at the center" like a differential. I'd have two chains, one on each side to each driven side of the rear axle. Then when I wanted to, I could either pin/bolt them together to lock the rear axle. I'd probably shoot for a 3:1 or 4:1 OD ration. I'm open to ideas?

Redneckcomputergeak (on youtube) set up his hydro mudder like that, except he used a straight axle in the back to lock the differential for more traction. People have set them up with two axles like you suggested also, but I think it's nicer to have a locked diff. As to longevity, I'm not sure. It certainly helps that you keep the transaxle clean to keep it cool, these hydros will burn up if they are caked in mud and overheat. It would certainly be cool to see someone else do it!

Adding on to what Richie said about cooling, one could always build a sort of blower shroud for the hydro trans. They usually have a fan on the input shaft meant to blow cool air into the cooling fins, and if you built a shroud to go around the fan and the cooling fins (like an air cooled engine) it would keep dirt and Mud out and keep cool air in. It'd be pretty neat to see someone do that.

My guess would be it would hold up good enough for driving around, but if your going to try pulling a load with it that way, it might be tough on things.

I'll keep holding out until I here someone chime in that's actually done it. If you have a link to his YouTube vid, please post it. I couldn't find one.

havent made something like that but have blown two hydros . an mtd hydro on a unmodded mower and a sears hydro on an off road mower. wore out the pump with 22" itp mud lights . i personally think that hydros are cheaply made , spicer transaxles have done better for me .